It was last night here on "world news," we reported on that headline the nazi next door in one american community, tonight, though, the new surprise on the same street, for neighbors there it's been an emotional 24 hours and here's abc's rob nelson. Reporter: Neighbors in this minneapolis community are comingrips with the news an alleged former nazi commander has been living among them for years. I'm sorry for his victims. I'm sorry for him. Reporter: An investigation by the associated press has concluded that this man, 94-year-old michael karkoc, was allegedly part of a nazi unit accused of burning villages and killing dozens of women and children in ukraine. We're learning some of his neighbors are holocaust survivors, including this woman's mother. We know them very well from churches, from activities, they're just aovely family. Reporter: Karkoc came to america in 1949 after reportedly lying about his military past. Get off the property now! Reporter: At first his family refused to talk to the media, now his son is blasting the investigation. My father was never a nazi. Reporter: For now, she doesn't know how to break the news to her 90-year-old mother. I don't know what to do at this point, I'm sorry to say. Reporter: When reached by the ap, karkoc said only quote, i don't think I can explain. He may now face the possibility of losing his citizenship, deportation and, david, even prosecution for war crimes.

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